Pin drill and end mill



Patented Jan. 22, 1946 UNITE-D. sures PATENT orrlce Application April 16, 1945, Serial No.'588,447 V In Sweden AugustlB, 1942 7 Claims.

The present invention relates to adjustable gcounterboresor pin drills, as well as end mills,

of thekind which are provided with two cutter tools whichare. slidably guided inthe head or bodyof the pin drill in such manner that said cutter tools may be displaced radially outwards in a plane diametral to the axis of the said body,

and may thus be adjusted, in any desired positions, by means of a wedge cooperating with said cutter tools. I

It is an object .of the present invention to pro,-

-vide an improved, simplified and strongv construction of a pin drill or end mill of this type,

in which the cutter tools shall be easily and yet accurately adjustable to any desired working-diameter within a large range of diameters. -It is also an object of the present invention to provide a construction in which the cutter tools are of a simple and comparatively inexpensive construction, and in which a change of cutter'tools is rigidly heldto the body of the pin drill when .in use, but which may easily be removed entirely so that the pin drill may be used as an end mill, or maybe replaced by another pilot having a difierentexternal diameter so as to render the pin drill adjustable to suit various dimensions of the hole into which the said pilot is to be inserted.

An important feature of the present invention is that the cuttertools are provided with flanges which extend laterally from the cutter tools, that is to say, in a direction transverse to the axis of the head or body of the pin drill, to

the exterior of said :body, and which flanges cooperate with the wedge which is slidable in a channel or keyway provided in the exterior surface of said body and extending in a direction parallel to the axis thereof; This construction provides for an easy-and convenient adjustment of the cutter tools. r

Other features of the invention will be readily apparent from the following description of a preferred constructional form of an adjustable counterbore or pin drill incorporating the features of this invention, and which is illustrated by way of example in the accompanying drawing.

In the drawing, Fig, 1 showsan elevation of the pin drill, and'Fig. 2 shows an end view of the same, while. Fig. 3 shows a section of the pin drill. on the line IIIII[ in Fig. 1.7 Fig. 4 shows a side viewof the pin drill, similar to Fig. l,

.- butwith the cutter; tools in expanded positions,

and. with certain parts removed. Fig. 5 shows an adjustment r the drill;

eievation of the wedge.v Figs. 6, 7 and 8 show a cutter tool viewed in elevation; side view and end view, respectively. Figs. 9 and 10 show a side View and an end view of a key used for V Fig. 11 shows a modified construction of the pilot of the pin drill. r The counterbore or pin'drill illustrated in the drawing is providedwith a head or body I having a shank} by means of which the pin drill may be inserted and clamped in a chuck of a turninglathe, a drillpress, a milling machine, or the like. Two cutter tools 3 and 4 areprolvided in the body I and are guided therein in a channel or guideway 5 formed between a guide jof, on the one hand, and on the other, an opposed guide surface I on the body I and a surface 8 n a cover plate or clamp piece 9, both of which surfaces 1 and 8 are also parallel to the axis of the body I. The cover plate 9 is retained'in position bearing against the cutter tools 3 and 4 and forcing them against the guide surface -6 by a screw III which is screw-threaded into the body I. The cover plate 9 is also held in positionby a ,dowel pin II which is inserted in the body I .and the outer end of which fits into a corresponding hole in the cover plate.

Each cutter tool 3 and 4 has aradial cutting edge l2 at its lower end anda longitudinal cutting edge I3 at its outer side. Each'cutter tool ,3 and 4 is also provided with a flange l4 and [5,

respectively, which projects laterally and at right .angles from the cutter tool at a distance from 35..

the inner or upper end of the cutter tool, as illusy trated in Figs. 3, 6, 7 and 8. Said flanges l4 and [5 are guided in a channel or guideway l6 formed between a guide surface 11 on the body I perpendicular to the axis thereof and a similar opposed guide surface ill on the cover plate 9, also perpendicular to the axis of the body I. In this way ,the said cutter tools 3 and 4 are efficiently guided 1 in the body assembly "of the pin drill, so that they may be projected or slid outwards from the axis of the drill or retracted within the body thereof. In the most retracted position of the said cutter tools 3 and 4, which isillustrated in F g. 1; the inner edgesof the cutter tools abut,

and for this reason each cutter tool is provided in its said inner edge with semi-circular recesses w I 9 and 20, Fig. 6, to provide clearance for the dowel pin II and for the screw Ill.

, The body I is provided with an outside groove or keyway 2| which extends in the axial direction of the said; body and which forms a guide for a wedge 22 which is slidable therein in the axial direction of the tool. The said wedge 22 is provided with a slot 23 which is traversed by a screw 24 which is screw-threaded into the body I, and the head of which bears against the outer surface of said wedge 22 and serves to clamp the wedge against the body I and to secure it in position. The wedge 22 is provided with two inclined wedge surfaces 25 which form equal angles to the axial direction of the wedge which is also the line of motion of the wedge in the keyway 2|. The said wedge surfaces 25 cooperate with the flanges I 4 and [5 on the cutter tools 3 and 4, respectively, and for this purpose the said flanges l4 and I5 are provided with bevelled surfaces 26 having the sameinclination to the axis of the tool as the said wedge surfaces 25' on c wedge 22 is displaced downwards from the position shown in Fig. -l, such movement of the wedge will cause the flanges 14 and I5 and thus also the cutter tools 3 and 4 to be displaced radially outwards due to 'thewedge surfaces 25 cooperating with the inclined surfaces '26 on the said flanges l4 and I5. In order to allow such outward movement of the cutter tools 3 an-d4, it is of course necessary first slightly'to unscrew .the' screw 13 to relieve the clamping pressure of the cover plate 9 onthesaid cuttertools 3 and 4 sufficiently to allow the said tools 3 and 4 to slide between the cover plate 9 and the body I, and it is als necessary slightly to'unscrew the screw 24 to relieve the pressure thereof on the wedge 22. 2

In order to provide for an easy and convenient adjustment of the wedge 22 there are provided a number of holes 21 in the body I, said holes being adapted to receive an eccentric pin 28 at one end of a key 29, which is illustrated in Figs. 9 and 10. The key 23 is provided with a cylindrical portion 38 adjacent the eccentric-pin 28, while the shaft of the key may have a polygonal and preferably hexagonal cross section. When the eccentric pin 28 is inserted in one of the holes 21, the key maybe turned about said pin as a pivot whereby th circumference of the cylindrical portion 39'wi ll cooperate with the end surface 31 f the wedge 22 so as to displace the latter in a downward direction, as viewed in Fig. 1, such downward movement of the wedge 22 resulting in the cutter tools 3 and 4 being separated and moved radially outwards from one another, as already stated. In this way, therefore, the pin drill may be easily and conveniently adjusted for various diameters. After such adjustment has been made, the screws l and 24 are of course pulled tight again, so as to retain the cutter tools 3 and 4, and the wedge 22, respectively, in their adjusted positions.

The heads of the screws l0 and '24 may suitably be provided with hexagonal recesses 32 adapted to receive the bent end 33 of the key 29, whereby the said screws may easily and conveniently be loosened and pulled tight by the aid of the said key29.

In the constructional form illustrated in Figs. 1 to 4 inclusive the pilot or guide pin 34 of the pin drill is formed as a separate member and is provided with a neck 35 having a smaller diameter, and a collar 36 at the inner end thereof. The body I is provided with a recess 31, Fig. 4, of a corresponding shape, and the cover plate 9 is also provided with a similar recess, said recesses serving to receive the said neck 35'and collar 36 of the pilot, so that in this way the latter may be retained in position between the ,with a hexagonal recess 32 to receive the end 33 of the key 29, as above explained in connection with the screws I0 and 24. The said ring 39 provides the actual guide surface of, the pilot. The pin drill is preferably provided with a plurality of interchangeable rings 39 having the same inner diameter adapted to lit the protruding portion of the pilot 34, but having different outside diameters. By selecting a ring having the proper outside diameter the pin drill is easily adjusted to suit the diameter of the hole into which the pilot is to be inserted. By removing the pilot 34 and the ring 39, the pin drill may be used .as'an end mill, as will be easily understood.

Fig. 11 shows a slightly difierent construction of a pilot or guide pin 44. Also in this :case the pilot is provided with .a neck45 .of .a smaller diameter and with a collar 46 similar to the neck 35 and collar .36 illustrated in Fig. 3, and with a slot 48 similar to the slot .38. In this case no surrounding ring is used on the protruding portion of the pilot, which is itself adapted .to serve as a guide for .the pin drill. In this case the spin drill will be supplied with a plurality of .such pilots 44 having different outside diameters of the protruding portion of the pilot, and which are interchangeable, so that a pilot having the proper diameter may "be selected andinserted between the body 'I and the cover plate 9.

I claim:

1. In a tool of th character described, the combination of a body, cutter tools slidable and adjustable in the diametral direction in said body, said cutter tools having flanges projecting therefrom in the transverse direction"ofrsaid-body to the exterior surface of said body, said body having a groove or keyway in its exterior surface extending in a direction parallel to the axis of said body, a wedge slidable in said keyway and provided with faces equally inclined to the longitudinal direction of saidwedge, said wedge being adapted to cooperate with said flanges on said cutter tools soas' thereby to displace said flanges and cutter tools away from one another in the diametral direction of said body, means for securing said cutter tools .inadj-usted positions, and means for securing said wedge in adjusted position.

2. In a tool of -thecharacter described, the combination of a body, a shank secured torsaid body and serving to secure the same in 2a chuck, said body having :a plane guide surface substantially parallel to the. axis of said body and said shank, said body having a plane guide surface'substantially perpendic'ularto. the lax-is thereof, ,a cover plate having two guide surfaces substantially perpendicula'r to one another, means for attaching said cover plate to said body .in such position that said surfaces on :said' cover plateiform together with said guide surface son said body a "substantially L-shaped channel :01 guidewayiin such assembly of said podyiandsaidlcover late; one per-V tion of said guideway beingiloc'ated substantially axially and diametrically-fin said assembly, and

gex'tending substantially perpendicular to such body portion and located; in the transverse; portion of such-guideway, isaidflanges on said cuttertoo'ls extending to'the' exterior of-said-body, said body having a groove-orkeyway in its exteriorisurfaceg extending in' a' direction parallel to the axis of said body, a wedge slidablyrgui'ded in said keyways'opas 'to be movable in a direction parallel to the axis of saidbody, said;wedge having two" facesequally inclined in oppositedirectionsto the line of motion of saidiwedge inssaid groove, "said inclined surfaces being adapted-:to cooperate with said flanges :on said cutter=tools so as thereby to displace said flanges andr-saidcutter tools away from one another in'.the diam-f etrali direction of c said body, and j means for securing said wedge in adjusted position relatively to said body.

3. In a tool of the character described, the combination of a body, a shank secured to said body'and serving to secure the same in a chuck, said body ,having a plane guide surface substantially parallel to the axis of said body and said shank, said body having a plane uide surface substantially perpendicular to the axis thereof, a cover plate having two guide surfaces substantially perpendicular to one another, mean for attaching said cover plate to said body in such position that said surfaces on said cover plate form together with said guide surfaces on said body a substantially L-shaped channel or guideadapted to bear against the outersurface of said wedge so" therebyito secure said 'wedge in; ad+ iu'ste'dpositionq I :91

4. In a'tool ofthe character described, the combination of a body', acover plate, cutter tools slidable. and adjustable'in the diametral direction between said body andsaid cover plate, said cutteritools having flanges projecting therefrom in the transverse directionflof. said; body to; the exterior surfaceiof said body; said body having a groove or keyway ,in' its-exterior surfacefextending in a dlrection-parallelto the axis of-Isaid body, a wedge slidable in said keyway andz-provided. with faces equally inclined to the longitudinal directioniofsaid-wedge, said wedge being adapted to. cooperate with said flanges on; said cuttertools-so as thereby to displace said; flanges an'dxcutter tools ;;away from one another in the Way in such assembly of said body and said cover plate, one portion of said guideway being located substantially axially and diametrically-in said assembly, and the other portion of said guideway extending in a transverse direction to the axis of such body to the exterior thereof, said means comprising a screw passing through a hole in said cover plate and screw-threaded into said body, a dowel pin secured to said body and passing through a hole in said cover plate, two cutter tools positioned in said guideway so as to be slidable and adjustable therein in a diametral direction relatively to the axis of said body, each of.

said cutter tools having a body portion located in the axially directed portion of said guideway and a flange extending substantially perpendicular to such body portion and located in the transverse portion of such guideway, said flanges on said cutter tools extending to the exterior of said body, said body having a groove or keyway in its exterior surface extending in a direction parallel to the axis of said body, a wedge slidably guided in said keyway so as to be movable in a direction 'parallel'to the axis of said. body, said wedge having two faces equally inclined in opposite directions to the line of motion of said wedge in said groove, said inclined surfaces being adapted to cooperate with said flanges on said cutter tools so as thereby to displace said flanges and said cutter tools away from one another'in the diametral direction of said body, said wedge having an elongated through slot extending in the I longitudinal direction of said wedge, and a screw passing through said slot in said wedge and screw-threaded into said body and having a head diametral direction of saidbody, means; for securing' 'said'wedge in adjusted position, means for attaching saidncoyer plate to said body, and a .pilot, said pilothaving a collar at one end thereo'f,:-,said body andsaid .cover plate havinglrecesses adapted pto, ireceivet said, end of said. Pi ot and said collar; thereon, said zpilot ,havinga' slot adaptedto accommodate said cuttertools; ,v'

5. In a tool of the character described, the combination of a body, a shank secured to said body and serving to secure the same in a chuck, said body having a plane guide surface substantially parallel to the axis of said body and said shank, said body having a plane guide surface substantially perpendicular to the axis thereof, a cover plate having two guide surfaces substantially perpendicular to one another, means for attaching said cover plate to said body in such position that said surfaces on said cover plate form together with said guide surfaces on said body a substantially L-shaped channel or guideway in such assembly of said body and said cover plate, one portion of said guideway being located substantially axially and diametrically in said assembly, and the other portion of said guideway extending in a transverse direction to the axis of such body to the exterior thereof, two cutter tools positioned in said guideway so as to !be slidable and adjustable therein in a diametral direction relatively to the axis of said body, each of said cutter tools having a bodyportion located in the axially directed portion of said guideway and a flange extending substantially perpendicular to such body portion and located in the transverse portion of such guideway, said flanges on said cutter tools extending to the exterior of said body, said body having a groove or keyway in its exterior surface extending in a. direction parallel to the axis of said body, a wedge slidable in said keyway and provided with faces equally inclined to the longitudinal direction of said wedge, said wedge being adapted to cooperate with said'flanges on said cutter tools so as thereby to displace said flanges and cutter tools away from one another in the diametral di-, rection of said body, means forsecuring said wedge in adjusted position, and a pilot, said pilot having a. neck of a smaller diameter and a. collar at the end of said neck, said body and said cover plate having recesses adapted to receive said neck portion and said collar on said pilot, said pilot having a slot adapted to accommodate said cutter tools. V

6. In a tool of the character described, the combination of a body, a shank secured to said body and serving tosecure the same in a chuck, said body having a plane guide surface substantially parallel to the axis of said body and said shank, said body having a plane guide surface substantially perpendicular to. the aims thereof, a cover plate having two guide surfaces substantially perpendicular to one another, means for attaching said cover plate to said body in such position that said surfaces on said cover plate form together with said guide surfaces on said body a substantially L-shaped channel or guideway in such assembly of said body-and said cover plate, one portion of said guideway being located substantially. axially and diametrically in said assembly, and the other portion of'said guideway extending in atransverse direction to the axis of such body to the exterior thereof, two cutter tools positioned in said guideway soas to be slidable and adjustable therein in a diametral direction relatively to the axis of said body, each of said cutter tools having abody portion located inthe axially directed portion of said guideway and a flange extending substantially perpendicular to such body portion and located in the transverse portion of such guideway, said flanges on said cutter tools extending to theexterior of said body, said body having a groove or keyway in its exterior surface extending in a direction parallel to the axis of said body, a wedge slidable in said keyway and provided with faces equally inclined to the 1on gitudinal direction of said wedge, said wedge being adapted to, cooperate with said flanges onsaid cutter tools so as thereby to displace said flanges and cutter tools away from one another in the diametral direction of said body, means for securing said wedge in adjusted position, a pilot, said pilot having a neck of a smaller diameter and a collar at the end of said: neck, said body and said cover plate having recesses adapted to receive said neck portion and said collar on said pilot, said pilot having a slot adapted to accommodate said cutter tools, a'ring surroundingsaidpilot, a retaining washer for said ring, and a screw screwthreaded into the end of said pilot to secure said washer thereto.

7. A tool as claimed in claim 1, in which the body is provided with holes in the keyway for the wedge, said holes serving to receive an eccentric pin at the end of a key provided with a cylindrical portion adapted to cooperate with the end of saidwedge. y

\ ERNST GUSTAV AXEL FLODMAN. 

